The impact of Medicaid expansion on trauma-related emergency department utilization: A national evaluation of policy implications.

ABSTRACT

BACKGROUND: The impact of the 2014 Affordable Care Act (ACA) upon national trauma-related emergency department (ED) utilization is unknown. We assessed ACA-related changes in ED use and payer mix, hypothesizing that post-ACA ED visits would decline and Medicaid coverage would increase disproportionately in regions of widespread policy adoption. METHODS: We queried the National Emergency Department Sample (NEDS) for those with a primary trauma diagnosis, aged 18 to 64. Comparing pre-ACA (2012) to post-ACA (10/2014 to 09/2015), primary outcomes were change in ED visits and payer status; secondary outcomes were change in costs, discharge disposition and inpatient length of stay. Univariate and multivariate analyses were performed, including difference-in-differences analyses. We compared changes in ED trauma visits by payer in the West (91% in a Medicaid expansion state) versus the South (12%). RESULTS: Among 21.2 million trauma-related ED visits, there was a 13.3% decrease post-ACA. Overall, there was a 7.2% decrease in uninsured ED visits (25.5% vs. 18.3%, p < 0.001) and a 6.6% increase in Medicaid coverage (17.6% vs. 24.2%, p < 0.001). Trauma patients had 40% increased odds of having Medicaid post-ACA (vs. pre-ACA aOR 1.40, p < 0.001). Patients in the West had 31% greater odds of having Medicaid (vs. South aOR 1.31, p < 0.001). The post-ACA increase in Medicaid was greater in the West (vs. South aOR 1.60, p < 0.001). Post-ACA, inpatients were more likely to have Medicaid (vs. ED discharge aOR 1.20, p < 0.001) and there was a 25% increase in inpatient discharge to rehabilitation (aOR 1.24, p < 0.001). CONCLUSION: Post-ACA, there was a significant increase in insured trauma patients and a decrease in injury-related ED visits, possibly resulting from access to other outpatient services. Ensuring sustainability of expanded coverage will benefit injured patients and trauma systems. LEVEL OF EVIDENCE Economic, level III.